When composing an email message, the message in progress is automatically saved to the composer's draft mail folder when the system detects no activity for a period of time (usually a couple of minutes). In addition, the composer has the option to explicitly save the email message into the draft folder. The composer can then retrieve the saved draft from the draft folder and finish the message. This is how most messaging systems are set up.
However, because the unfinished messages are out of sight, email users generally forget about the unfinished drafts and begin new email messages. Consequently, the draft messages proliferate in the draft folder. The user might also end up losing the context of the draft after a long period. Users tend to compose mail and then save the mail as drafts to be sent later. Seldom do they send all the drafts which were written, for an assortment of reasons, including:
1) users want certain emails to be sent out at a specific time and they subsequently forget to send; and
2) some temporary internet connection error might occur on the user's side and they are not aware that the email was saved as a draft and not sent.